Image volume browser with variably adjustable orientation measurement

ABSTRACT

A method, a monitor control module and system are disclosed for displaying a medical image from a volume dataset on a monitor of a computer-aided device, whereby, in addition to the image a number of orientation images from the volume dataset are to be displayed. In at least one embodiment, the user determines an orientation measurement beforehand, on the basis of which orientation images will be selected from the volume dataset and presented for display with the image. The orientation measurement can be either based on distance or be the result of an anatomic model.

PRIORITY STATEMENT

The present application hereby claims priority under 35 U.S.C. §119 onGerman patent application numbers DE 10 2009 006 148.7 filed Jan. 26,2009 and DE 10 2009 004 005.6 filed Jan. 7, 2009, the entire contents ofeach of which are hereby incorporated herein by reference.

FIELD

At least one embodiment of the invention lies in the field of medicalinformation technology and relates in particular to the display ofmedical slice images from a volume dataset.

BACKGROUND

Modern imaging methods in medical technology mean that a doctor, whileundertaking a diagnosis for example, is confronted by a plurality ofsectional images that he must evaluate. Looking through large numbers ofsuch sectional images is very tiring and as such is liable to errors. Onthe other hand very great care has to be taken during this task, sincethe result generally has a decisive effect on the further treatment ofthe patient.

The desire is accordingly to improve the display of sectional imagedata. In particular an orientation in a three-dimensional space and inrelation to the human body is to be made easier.

In the prior art the practice of displaying additional furtherorientation images in addition to the image to be displayed or thesectional image on which the examiner is currently concentrating isknown. Thus a method from the prior art typically aims to present threecorrelated views, each orthogonal to each other, which mutually serve asan overview. The orientation images also serve to make the environmentof the respective image and relevant anatomic structures rapidlydetectable.

Image browsers are also known in the prior art which make it possible toswitch back and forth or to scroll between individual images. To obtainan overview of the anatomic structure of the image to be displayed, itis thus known that a switch can be made from the (current) image to bedisplayed to further images. The further images to which the user canswitch are selected from a volume dataset in accordance with a rigidpre-configurable scheme. For example each adjacent fifth, tenth orfifteenth image can be retrieved for further display in relation to the(current) image, so that the user can then switch from the current imageto the adjacent images. The disadvantage associated with this is thatthe doctor, for the purposes of better orientation, must perform amanual user interaction (which once again diverts him from his work), sothat he cannot automatically obtain any combined display of the imageand the further images.

Although the prior-art browsers mentioned above do offer the user adegree of assistance in orientation—they are also still associated withfurther disadvantages. On the one hand orientation in the overall volumedataset is only possible with difficulty, since this typically consistsof hundreds of individual sectional images. In other words a very largenumber of sectional images must be viewed. Another disadvantage is thatthere is no variable adjustment available to the user, but rather thefurther images that are to be displayed for the current image aredefined in the same way in each case. If the volume dataset for a CTexamination relates for example to the entire stomach area of a patientand if only the area of the porta hepatis is of interest clinically,with the previous browsers the doctor had to view a plurality ofsectional images and so-to-speak “work towards” the image with the portahepatis. In doing so he must orient himself in the large volume ofsectional images in order to arrive at the relevant area. It is easy tosee that this method—especially with complex circumstances—is veryliable to errors and is inefficient.

SUMMARY

In at least one embodiment of the present invention is therefore todemonstrate a way in which the orientation and the overview in thedisplay of medical images from a volume dataset can be improved. Inaddition finding relevant structures in the volume dataset is to besimplified and speeded up. In particular it is to be possible explicitlyto access or find an anatomic structure in the display of images fromthe volume dataset, so that further processes (a diagnosis or study onthe part of the doctor) are less liable to errors.

At least one embodiment of the inventive method will be described below.Features, advantages or alternate embodiments are also mentioned here.In other words the physical aspects (which are typically directed to asystem, a device or a product) can also be developed with the featureswhich are described or claimed in connection with the method. Thecorresponding functional features of the method are embodied in suchcases by corresponding physical modules, especially by hardware modules.

At least one embodiment of a method is for displaying at least onemedical image from a volume dataset, whereby the image is to bedisplayed on a monitor of a computer-aided device and whereby inaddition to the image, a number of orientation images from the volumedataset of the image are to be displayed, comprising:

-   -   Determination of an orientation measurement or provision of a        predetermined orientation measurement;    -   Application to the volume dataset of the orientation measurement        determined or provided, in order to select from the volume        dataset the orientation images which correspond to the        orientation measurement determined or provided;    -   Display of the image together with the selected orientation        images.

The technical terms used within the framework of embodiments of thisinvention will be explained in greater detail below.

The term “display” relates to a display of datasets especially imagedatasets, on a screen or monitor. The display can relate to the entiremonitor but also to only a part of the monitor, and is typicallydirected for example to display in a window. The image is displayed on amonitor of the computer-aided device.

The computer-aided device can involve a medical workstation, a desktopcomputer, a portable computer or other mobile devices (PDAs etc.). Thedevice can involve an operating console of imaging apparatus (CT, MRT,ultrasound etc.).

At least one embodiment of the invention makes a distinction between theterms image, orientation images and navigation images. The term imagerelates to the current image or image to be displayed which is ofcentral interest to the examiner. The orientation images provide theexaminer with an orientation aid and comprise information about thespatial position of the respective image within the volume dataset. As arule a number of orientation images are displayed for the image. Inexceptional conditions it may however also be possible to display only asingle orientation image, as a comparison image so to speak.

The orientation images always have a relationship to the image (to bedisplayed), since they are intended as an overview and possiblyadditionally as an orientation aid for the respective image. In otherwords there is an assignment between image and respective orientationimages so that, on a switch from a first image to a second image, aswitch is also made between the respective orientation images (forexample from a first set of orientation images to a second set oforientation images).

The navigation image is an overview display and is used for improvednavigation between the individual images and for improved orientation.The navigation image can be displayed automatically or if necessary inresponse to a signal as an additional aid to the examiner in order toshow an overview display of the three-dimensional volume datasetrecorded. In accordance with the preferred embodiment the navigationimage is provided with position markings for the respective orientationimages and/or with position markings for the image. The navigation imagecan be two-dimensional or three-dimensional. Usually the navigationimage is a reconstruction image orthogonal to the image and/or to theorientation images.

The orientation measurement involves a function which is applied to thethree-dimensional volume dataset in order to segment or classify thelatter into specific areas or sections. The orientation measurement is aselection scheme and is designed to be used as a basis for a(user)-configurable selection of orientation images from the volumedataset as an orientation overview. The display of the orientationimages in addition to the image enables an improved orientation to beachieved.

In accordance with an example embodiment of the invention two differentmeasures of orientation are provided. The orientation measurement canthus firstly involve a distance-related orientation measurement, withthe spacing of the orientation measurement identifying the distance ofthe respective orientation image from the image (to be displayed). Inaddition the orientation measurement can secondly also be anatomyrelated. The anatomy-related orientation measurement is based on ananatomic model which makes it possible to explicitly find relevantanatomic structures in the image stack.

To this end all or selected slices of the volume dataset are assigned ananatomic code from a controlled medical vocabulary. For example allorganic structures which belong to the liver are identified by the code“liver” and all anatomic structures which belong to the pancreas areidentified by the code “pancreas”. The relevant anatomic structures areselected on the basis of the anatomic model. In order to do this, theanatomic model takes into account metadata relating to the examinationand/or the patient. In particular the anatomic model takes account ofthe anatomic size conditions, depending on height, weight, age, genderand further metadata in relation to the patient. In addition theclinical problem and the type of examination (CT, MRT, US etc.) can betaken into account.

In accordance with an example embodiment of the present invention a userinterface is provided via which the user can set particular parametersbeforehand for the display. Cumulatively or alternately a furtherinterface can be embodied (or the existing interface can be expandedaccordingly) via which the further parameters can be set which can bederived from a workflow context within the framework of which the imageis to be displayed. This has the advantage of enabling support which isas automated as possible to be provided, with for example parameters forthe display of the images being able to be derived automatically for thedisplay with the selected orientation images from the higher rankingworkflow.

In particular he can specify here the anatomic structures that heregards as relevant and that are therefore to be taken into account inthe anatomic model. For example he can select here that only one choiceof anatomic structures is to be displayed. The anatomic model is thenapplied to the volume dataset to select the orientation images for theimage and display them. Preferably on the basis of the anatomic model(which takes account of metainformation, a distance of the relevantstructures from the image is calculated. Then all those sectional imagesfrom the 3D dataset are determined that are at the calculated distancefrom the image and these will be displayed as orientation images for theimage.

In accordance with an example embodiment of the present invention thedistance for the distance-based orientation measurement can be set toincrease. In other words a configurable growth parameter can be takeninto account that indicates with which factor or growth parameter thedistance from the orientation images to be displayed grows in relationto the image. The growth parameter is preferably preset or is derivedfrom the context (workflow).

Alternately it can also be entered manually by the user. Preferably itis preset here that the orientation images that are located close to theimage are displayed with a smaller distance and the orientation imageswhich are located further away from the image are displayed with agreater distance. The result of this is that the core area of interest,which, although it lies on the image with relatively many neighboringimages, is shown in great detail and that the number of orientationimages decreases all the more, the further away one is from the currentimage. The advantage of this is that the user is only given the relevantinformation and is not confronted with a plurality of unnecessaryslices. In an alternate embodiment the distance between the respectiveorientation images can however also be selected as constant or it canalso be determined manually by a corresponding interface and a userinput.

In a further variant the distance between the orientation images is alsoable to be configured for the anatomy-related orientation measurement.

In accordance with a further embodiment of the present invention, inaddition to the display of the image with the orientation images, anavigation image is also displayed. In this case it is possible toselect the times at which the different images are displayed. On the onehand it is possible for all orientation images to be displayed at thesame time as the image. Alternatively orientation images can bedisplayed only after a period of time or in response to a user action.Likewise the navigation image can be displayed at the same time as or inparallel to the display of the image and/or the display of theorientation images. Alternatively the navigation image can also bedisplayed offset in time at a later time, for example initiated by auser interaction (e.g. a corresponding confirmation signal).

According to an example embodiment the inventive system includes a userinterface which makes it possible to determine display parameters. Thedisplay parameters are use for configuration of the display of theimage, of the orientation images and/or of the navigation image. In suchcases different display parameters can also be defined for image,orientation images and navigation image. The display parameterstypically involve the size of the display, the position of the displayon the monitor, the resolution of the images, contrast parameters, thetime of the display, the thickness of the display, if a number ofsectional images are to be displayed for display superimposed as a 3Dimage stack with a specific thickness.

In accordance with a further advantageous embodiment of the inventionthe navigation image is interactive. In other words a correspondingdisplay or a change to the display can be achieved via correspondingsignals of the user within the navigation image. It is thus possible forthe user to use the navigation image interactively to navigate in thevolume dataset. If for example he chooses a specific image or a specificrange in the navigation image, this automatically leads to the assignedimage with its orientation images being loaded and displayed. In thiscase it is possible for the user to select a sectional image in thenavigation image so that the corresponding image with its orientationimages will be loaded. Likewise it is also possible for the user toactivate a range within the navigation image. This leads to all imageswith respective orientation images being displayed that are assigned tothis range.

In accordance with an advantageous development of at least oneembodiment of the present invention there is provision for thenavigation image to be three-dimensional and for simplified use for ananatomic structure to also be able to be incorporated or stored in thethree-dimensional display. This makes it possible for the userimmediately and so to speak at a glance to recognize the underlyinganatomic structure in each case. Overall this also leads to a markedreduction in errors in the subsequent diagnosis or study of the imagematerial. In accordance with a simple alternate embodiment thenavigation image is merely two-dimensional. Here too an anatomicstructure—as a two-dimensional image—can be shown.

As already mentioned, the display of the image with its orientationimages and the display of the navigation image occur at the same time.This has the advantage of the user having all the necessary informationto hand immediately and directly and not having to make any furtherseparate user entries. As an additional orientation aid the imageincludes a reference to its position in the navigation image. Inaddition it is also possible for all orientation images for the image tobe identified by such references, so that the position of the respectiveorientation images within the volume dataset is also indicated.Preferably this can be performed with a reference e.g. with arrows in agraphical display or with other assignment references.

So that the method is able to be adapted in the optimum possible way tothe respective application there is provision, as well as the displayparameters, for further factors to also be able to be taken into accountin order to configure the display. The factors in this case can beobtained automatically by the system, can be preset or can be set by theuser. Thus it can be set for example that initially a first number oforientation images are displayed for the image and that in a later phaseanother, as a rule smaller number of orientation images is displayed forthe image. This has the advantage that the number of relevant images canbe reduced within the framework of the ongoing inspection process, sinceas a rule the focus can be set more narrowly as the display proceeds.

A further significant aspect of an embodiment of the present inventionis also to be seen in the fact that the method is able to be integratedinto a medical workflow so that, depending on the alignment of themedical workflow, the display process can be specifically tailored. Forthis purpose automatic default settings are made for displaying theimage along with the orientation images and where necessary thenavigation image. These defaults are based on metainformationcomprising: The type of examination and the clinical problem. If forexample the clinical problem relates to the clarification of an icterus(jaundice) and a computed tomographic image of the abdomen has beencreated, it can be automatically derived from this metainformation thatfor example the porta hepatis and the pancreas head are of outstandingsignificance and should also be displayed.

The automatic configuring of the inventive display process on the basisof context information (metainformation) is undertaken by accessing arule base in which medical knowledge is stored. Knowledge fromguidelines can also be stored in the rule base.

The image to be displayed can either be displayed as a two-dimensionalsectional image or as a three-dimensional image. If the image is to bedisplayed as a three-dimensional image, a so-called multi planarreformatting is executed. In other words a number of sectional imagesfrom the volume dataset are calculated in combination and are to bedisplayed as a combined three-dimensional overall image. For this therespective origin images are superimposed and a three-dimensionaloverall image is computed.

This method is especially suitable for recognizing specificthree-dimensional structures within the volume dataset, since specificstructures can be more easily recognized in a three-dimensional displaythan in a two-dimensional display or than in a sequence oftwo-dimensional displays. Thus if the image to be displayed isthree-dimensional in this embodiment the defaults can be selected forhow many slices are to be included for display. Optionally theorientation images can then be two-dimensional or three-dimensional.Usually three-dimensional orientation images will also be displayed fora three-dimensional image.

However it is possible to configure how many slices are included for thedisplay of the orientation images. In particular the thickness of theimage can be set differently and separately from the thickness of theorientation images. Usually the slice thickness increases with thedistance from the image (to be displayed). In other words the display inthe center around the image to be displayed is very detailed and becomesever coarser as the distance from this center increases.

A further solution to the problem is provided in a monitor control modelfor controlling the display of the medical image on the monitor.

A system is also disclosed for displaying at least one image from thevolume dataset.

A computer program product and a storage medium are also disclosed, thatare embodied for executing the method described above when the programis executed on a computer.

With at least one embodiment of the inventive solution, a series ofadvantages can be achieved. Thus it is significantly easier for theexaminer to provide himself with an overview of the overall situation.In addition he can find the relevant images for a clinical problem muchmore quickly without being unnecessarily diverted by a flood of imagedatasets. In addition orientation is made easier by orientation imagesbeing displayed from the surroundings of the respective image along witheach image. This means that the danger can be greatly reduced ofinadvertently overlooking relevant structures. In addition thenavigation in the volume dataset is significantly simplified since therespective image positions in the navigation image are able to bedetected at a glance. In addition specific anatomic structures can belooked for quite explicitly. This is especially possible through theapplication of the anatomy-related orientation measurement which makesit possible to enter specific anatomic structures (e.g. liver, kidneys,stomach) so that exactly the structures entered are taken into accountin the display.

BRIEF DESCRIPTION OF THE DRAWINGS

In the detailed description of the figures given below exampleembodiments, which are not to be understood as being restrictive, willbe discussed with their features and further advantages with referenceto the drawing. The figures are as follows:

FIG. 1 shows an overview-type diagram of orientation images withconstant spacing, an image and a navigation image which refers to anexample;

FIG. 2 shows an overview-type diagram of orientation images, based on ananatomy-related orientation measurement in accordance with anadvantageous embodiment of the invention which refers to an example;

FIG. 3 shows a schematic diagram of an image, a number of orientationimages with increasing spacing and a navigation image according to anexample embodiment of the invention.

FIG. 4 shows a schematic diagram of an image, a number of orientationimages and a navigation image for an MPR display with increasing scopein accordance with an advantageous embodiment of the present invention.

FIG. 5 shows an overview-type schematic diagram of individual modules ofan inventive system, as can be employed in a further example embodiment.

DETAILED DESCRIPTION OF THE EXAMPLE EMBODIMENTS

Various example embodiments will now be described more fully withreference to the accompanying drawings in which only some exampleembodiments are shown. Specific structural and functional detailsdisclosed herein are merely representative for purposes of describingexample embodiments. The present invention, however, may be embodied inmany alternate forms and should not be construed as limited to only theexample embodiments set forth herein.

Accordingly, while example embodiments of the invention are capable ofvarious modifications and alternative forms, embodiments thereof areshown by way of example in the drawings and will herein be described indetail. It should be understood, however, that there is no intent tolimit example embodiments of the present invention to the particularforms disclosed. On the contrary, example embodiments are to cover allmodifications, equivalents, and alternatives falling within the scope ofthe invention. Like numbers refer to like elements throughout thedescription of the figures.

It will be understood that, although the terms first, second, etc. maybe used herein to describe various elements, these elements should notbe limited by these terms. These terms are only used to distinguish oneelement from another. For example, a first element could be termed asecond element, and, similarly, a second element could be termed a firstelement, without departing from the scope of example embodiments of thepresent invention. As used herein, the term “and/or,” includes any andall combinations of one or more of the associated listed items.

It will be understood that when an element is referred to as being“connected,” or “coupled,” to another element, it can be directlyconnected or coupled to the other element or intervening elements may bepresent. In contrast, when an element is referred to as being “directlyconnected,” or “directly coupled,” to another element, there are nointervening elements present. Other words used to describe therelationship between elements should be interpreted in a like fashion(e.g., “between,” versus “directly between,” “adjacent,” versus“directly adjacent,” etc.).

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of exampleembodiments of the invention. As used herein, the singular forms “a,”“an,” and “the,” are intended to include the plural forms as well,unless the context clearly indicates otherwise. As used herein, theterms “and/or” and “at least one of” include any and all combinations ofone or more of the associated listed items. It will be furtherunderstood that the terms “comprises,” “comprising,” “includes,” and/or“including,” when used herein, specify the presence of stated features,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof.

It should also be noted that in some alternative implementations, thefunctions/acts noted may occur out of the order noted in the figures.For example, two figures shown in succession may in fact be executedsubstantially concurrently or may sometimes be executed in the reverseorder, depending upon the functionality/acts involved.

Spatially relative terms, such as “beneath”, “below”, “lower”, “above”,“upper”, and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. Thus, term such as “below” can encompass both anorientation of above and below. The device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein are interpreted accordingly.

Although the terms first, second, etc. may be used herein to describevarious elements, components, regions, layers and/or sections, it shouldbe understood that these elements, components, regions, layers and/orsections should not be limited by these terms. These terms are used onlyto distinguish one element, component, region, layer, or section fromanother region, layer, or section. Thus, a first element, component,region, layer, or section discussed below could be termed a secondelement, component, region, layer, or section without departing from theteachings of the present invention.

The basic principle of at least one embodiment of the present inventionwill be described below.

As part of a medical task a doctor would like to view image material. Tothis end an image B is loaded onto a monitor M of a computer-aidedsystem. Since the image datasets as a rule have a very high volume ofdata it is necessary for the doctor to know his way around within theplurality of the slices displayed of be able to orient himself andnavigate within them.

This work is very tiring since the doctor is confronted with a pluralityof image contents which in some cases only differ from each othermarginally, so that a very attentive and specific viewing is required.In addition an orientation based on the type of examination (e.g. CT,MRT etc.) is in some cases only possible with great difficulty and as arule the doctor needs a degree of expert and empirical knowledge to beable to recognize the anatomic structure to which the respective slicebelongs.

This is the starting point of an embodiment of the present invention.Inventively not only the current image B to be displayed will bedisplayed. Inventively there is provision that, as well as the currentimage B, further image contents will also be displayed for improvedorientation on the monitor M.

In accordance with a first embodiment there is provision that, inaddition to the image B, orientation images OB will also be displayed onthe monitor M. The orientation images OB involve images adjacent to orsurrounding the image. If the image B changes, the orientation images OBdisplayed also change. As well as the current image B on which the focusof observation of the examiner lies, a selection of ambient imagesarranged before and/or afterwards in relation to the image B will alsobe displayed. Preferably the orientation images OB can be displayed asthe distance from the image B increases. The advantage of this is thatin the immediate vicinity of the image B to be observed, which lies inthe focus of the interest, a more detailed display can be achieved,while it becomes ever coarser as the distance from the image Bincreases.

As an alternative it is possible to display orientation images OB with aconstant distance from image B. This is shown in FIG. 1. An embodimentis shown in FIG. 1, which in addition to the image B and the orientationimage OB, also shows a further display. This further display relates toa navigation image NB. In the navigation image NB which is shown in FIG.1, the constant spacing between the images B, OB displayed can be seenin each case. All orientation images OB displayed here are spaced at aconstant distance from image B.

The navigation image NB is intended as an overview image and the contentdisplayed in the navigation image NB is orthogonal to the content whichis displayed in the image B.

Usually the image B and the orientation images OB assigned to it involveindividual, parallel slices of the volume dataset. The navigation imageNB represents the volume dataset and additionally comprises anassignment to the image B/or to the orientation images OB. Thenavigation image NB can be a miniaturized display or a simplifiedrepresentation of the volume dataset. The simplified representation canbe calculated separately.

As can be seen from the figures, this assignment can be undertaken inthe form of arrows which are displayed on the monitor M. In this casethe arrows point from the image B and/or from orientation images OB tothe respective assigned layer image in the navigation image NB. Thearrows thus specify the spatial position of the image B and/or of theorientation images OB within the navigation image NB. Other embodimentsof the invention provide other forms of assignment (and no arrows) suchas colored outlines, colored markings, single dashes or lines orcross-hatching or other optical references.

As shown in FIG. 2, the user can at any time very rapidly and simplyobtain an overview of where and especially in which anatomic structurehe is currently located and which anatomic structures are affected bythe likewise displayed orientation images OB.

The display of the navigation image NB is however facultative and doesnot absolutely have to be displayed. It is also possible for the user tobe able to initiate the display of the navigation image NB with acorresponding user interaction.

The display of the orientation images OB in addition to the image B caninventively be based on various models. The first model is the so-calleddistance-based model. This model will also be referred to in thisapplication as a distance-based orientation measurement. The secondmodel is an anatomy-based model. Within the framework of at least oneembodiment of the invention this second model will be referred as ananatomy-related orientation measurement.

These two models will be explained in greater detail below. In alternateembodiments a combination of the models previously mentioned can also beused. In addition other models can also be employed which are based on amultidimensional display for example or which are aligned towardsthroughput speeds or other types of functional imaging. With thedistance-related orientation measurement a distance is pre-specified.This distance identifies how far the respective orientation images OBare to be from the current image to be displayed B. In other words thedistance relates to the measure of distance between the image B and theorientation images OB assigned to it.

Precisely this distance, which is shown in the navigation image NB inFIGS. 1 to 4, is also reflected in the slices. In FIG. 1 this distanceis constant. In other words, the image B and the orientation images OBeach have a constant spacing. In the navigation image NB those sectionalimages for which an image B or an orientation image OB is displayed areshown highlighted. In FIGS. 1 and 2 the displayed sectional images arehighlighted by highlighted identification of the respective sectionalplane. Alternately other types of highlighting (e.g. color etc.) can beselected here. To make for an easier assignment between image B ororientation image OB respectively and their position within thenavigation image NB, arrows are provided which point from the image B orfrom the respective orientation image OB to the sectional plane withinthe navigation image NB.

A significant feature of an embodiment of the present invention is to beseen in the fact that variable selection is possible as to whichorientation images OB are to be displayed for the respective image B.The user can determine here in the individual case how many orientationimages OB he would like to have displayed to him, at what size he wouldlike to see said images and with what spacing or of which anatomicstructures the orientation images OB are to be created.

Thus, depending on application, specific orientation images OB areselected from the volume dataset, so that they will be additionallydisplayed for the image B. The selection criteria can be varied in suchcases. It is thus possible for example for the spacing—as shown in FIG.1—to be constant.

As an alternative the spacing can be set with a constant growth factor,so that the orientation images will be displayed with an increasingspacing from image B. This is shown by way of example in FIG. 2.

In alternate embodiments, as well as the constant growth factor, anothergrowth factor can also be set. In addition it is possible for the userto select the orientation images OB manually. This can be done forexample by the user selecting a position within the navigation image NB.Then, on the basis of this selection the sectional image located thereis displayed as a further orientation image OB. In the latter case thedisplay of the navigation image NB is interactive, so that the user canselect a position using a specific signal (e.g. a mouse click). Thisthen automatically leads to the selected position leading to a choice ofa sectional image of the volume dataset, and to this sectional imagethen being displayed as an orientation image OB.

By contrast with the distance-based orientation measurement describedhere, the anatomy-related orientation measurement can be employed as analternative. With the anatomy-related orientation measurement anatomicstructures can be automatically identified and selected in advance orselected by the user, as “target structures” so to speak.

Typically this can be done via a confirmation signal in response to anentry in a list displayed at the user interface. A set of anatomicfeatures can be displayed in this list for example, from which the usercan select all or a selection as relevant, e.g.: liver (upper part),liver (lower part), pancreas head, aorta etc.

Alternately the anatomic structures can be identified as relevant on thebasis of the acquired metadata in an automated fashion in the header ofthe acquired image data. For example on the basis of the DICOM Attribute“Procedure Code” and/or “Reason for Study”. Accordingly images withinthe current image datasets, which have been acquired from the modalityin this context, are provided on the basis of the anatomic model withanatomic codes for the relevant anatomic “target structures” (e.g. usingthe DICOM “Primary Anatomic Structure Sequence”, which can contain oneor more anatomic codes per image).

As an alternative or cumulatively thereto an expert system module can beused in order to assign the slices to an anatomic structure. In otherwords one or more structure(s) can initially be identified by the user(e.g. by setting a marking and assigning a code) or an automaticdetection of at least one structure can be undertaken (e.g. bysegmentation and/or known mechanisms for pattern recognition). On thisbasis other structures and the codes assigned to them will be providedautomatically for the purposes of navigation based on the model inrelation to these initially detected structures.

Within the framework of an embodiment of the present invention ananatomic model will be made available that takes account of therelationship between anatomic variables, which are dependent on height,weight, age, gender and further parameters of the respective patient.Statistical values are also included here, so that the anatomic modelcan include the following information:

“For a male patient of height x, weight y, age z, the pancreas head ison average, in relation to a y-axis through the body, w centimeters awayfrom the kidney”. The anatomic model is preferably stored in thedatabase and can be applied via the suitable queries.

If the doctor has now identified specific anatomic structures in advanceas relevant or if these are detected automatically on the basis ofmetadata of the examination performed, there is initially access to theanatomic model with the spatial relationships of the relevant anatomicstructures. These structures will then be selected automatically in thevolume dataset—as described above—by means of anatomic codes anddisplayed as orientation images OB. Preferably all the method stepsgiven here occur automatically, i.e. without user interaction.

In the example depicted in FIG. 2 the image B relates to a pancreashead. The image B is shown in FIG. 2 in the third position. A number oforientation images OB is displayed for this image B. In FIG. 2 in theorientation images OB, seen from right to left, the upper part of theliver, the truncus coeliacus, the pancreas head and the aortabifurcation are to be typically displayed. Both the image B and also theorientation images OB are provided with arrows which are designed toindicate their respective position within the navigation image NB. Theyrefer to the respective sectional image that is represented highlightedin the navigation image NB (in FIGS. 1 and 2 by the lines runningvertically within the navigation image NB.)

Shown in FIG. 3 is a schematic display of the image B, of the assignedorientation images OB and the navigation image NB, with the orientationimages OB being selected with an increasing distance from image B. Inthe example in FIG. 3 the image B is shown as the largest image, whilethe orientation images OB are shown as being ever smaller the greaterdistance they are from image B. The advantage of this is that the mostimportant images (in the vicinity of the focus of interest) are shownlargest and the most unimportant image contents are shown smallest. Boththe image B and also the orientation images OB again include referencesto their spatial position within the navigation image NB. As can be seenfrom FIG. 3, the distance between the orientation images OB becomes evergreater towards the outside. In the example depicted in FIG. 3 both theimage B and also the orientation images OB are two-dimensional.Accordingly the references (arrows) point to individual slices withinthe volume dataset or within the navigation image NB.

In an alternate embodiment of the invention so-called multi planarreformatting is to be used as a basis for the display of the image Band/or of the orientation images OB. As an alternative to multi planarreformatting, other methods for generating three-dimensional views(which are subviews for the volume dataset so to speak) can also beused. In multi planar reformatting a number of slice datasets are mergedand a mathematical superimposition of the respective slice datasets iscomputed in order to generate a three-dimensional slice stack of aspecific thickness. The slice stack is able to be preset in accordancewith a preferred embodiment of the present invention. In particular theslice thickness of image B can be set independently of the slicethickness of the orientation images OB.

A typical display of image B and orientation images OB which are basedon the multi planar reformatting described above is depictedschematically in FIG. 4. In this embodiment a setting can be made inadvance as to whether the image and/or the orientation images OB are tobe displayed as two-dimensional or three-dimensional. In this example athree-dimensional display of the image B has been selected.Independently of this it can likewise be selected whether theorientation images OB for the three-dimensional image B are to bedisplayed as three-dimensional or two-dimensional images. In the exampleshown in FIG. 4 the orientation images OB are also depicted as an imagestack and thereby as three-dimensional images. Accordingly the arrowsgoing out from the image B and the orientation images OB do not point toindividual slice images but to blocks of slices. This is represented inFIG. 4 by the highlighted cubes or blocks within the navigation imageNB.

All the modalities for display mentioned above can also be combined withone another. It is thus possible for example that in each of thepreviously mentioned embodiments the user also has the additionalopportunity of selecting individual slices manually from the navigationimage NB, so that these will then be displayed as an orientation imageOB.

Navigation in the image stack (volume dataset) can be undertaken forexample via scrolling, clicking on the adjacent images or on a desiredposition within the image stack.

With the interactive design of the navigation image NB it is possible tofind relevant anatomic structures in a very efficient manner.

A major advantage of an embodiment of the inventive solution can be seenin the fact that the form of the navigation is user-specificallyconfigurable. Thus the doctor can select for example whether he wouldrather navigate on the basis of physical distances or whether herequires an anatomy-based navigation. In addition a combination ofdistance-based and anatomy-based navigation is also possible.

FIG. 5 is designed to show a schematic diagram of a structure of aninventive system 10 in accordance with a preferred embodiment of thesystem. The system comprises a unit which comprises a monitor controlmodule 11. The monitor control module 11 is used to control the displayof slice datasets of a volume dataset on the monitor M of thecomputer-aided system. The unit into which the monitor control module 11is integrated or the monitor control module 11 itself access metadata 12and/or display parameters 14. The metadata 12 and the display parameters14 can be stored in the same or in different databases. The metadata 12typically involves information such as:

Gender of the patient age, size, previous illnesses, previous medicalhistory, examination types (CT, MRT, US etc.), which had previously beencarried out, a clinical problem in relation to the patient etc. Thedisplay parameters 14 relate to all parameters in relation to thedisplay of the image B, of the orientation images OB and/or navigationimage NB. The display parameters 14 can match or can be different forthe image B, the orientation images OB and for the navigation image NB.

In particular settings can be made here for the size of the display, atthe size of the window, the type of highlighting of the slice images inthe navigation image NB, contrast defaults etc. In FIG. 5 the arrowwhich points to the unit from above which includes the monitor controlmodule 11 is intended to indicate that there is also provision here foruser inputs via a corresponding user interface, so that the user canmake entries to control the system. These entries can for example relateto the display parameters 14.

In addition the user can make entries in respect of the orientationmeasurement to be selected. As shown in FIG. 5, the inventive monitorcontrol module 11 can also be integrated into a more complex system 10which is designed to be more comprehensive for example and is based onthe computer-aided execution of a medical workflow.

Finally it should be pointed out that the description of the inventionand the example embodiments are not to be understood as being basicallyrestrictive in respect of a specific physical realization of theinvention. For an appropriate person skilled in the art it is especiallyevident that the invention can be realized partly or completely insoftware and/or hardware and/or distributed between a number of physicalproducts—especially also computer program products.

The patent claims filed with the application are formulation proposalswithout prejudice for obtaining more extensive patent protection. Theapplicant reserves the right to claim even further combinations offeatures previously disclosed only in the description and/or drawings.

The example embodiment or each example embodiment should not beunderstood as a restriction of the invention. Rather, numerousvariations and modifications are possible in the context of the presentdisclosure, in particular those variants and combinations which can beinferred by the person skilled in the art with regard to achieving theobject for example by combination or modification of individual featuresor elements or method steps that are described in connection with thegeneral or specific part of the description and are contained in theclaims and/or the drawings, and, by way of combineable features, lead toa new subject matter or to new method steps or sequences of methodsteps, including insofar as they concern production, testing andoperating methods.

References back that are used in dependent claims indicate the furtherembodiment of the subject matter of the main claim by way of thefeatures of the respective dependent claim; they should not beunderstood as dispensing with obtaining independent protection of thesubject matter for the combinations of features in the referred-backdependent claims. Furthermore, with regard to interpreting the claims,where a feature is concretized in more specific detail in a subordinateclaim, it should be assumed that such a restriction is not present inthe respective preceding claims.

Since the subject matter of the dependent claims in relation to theprior art on the priority date may form separate and independentinventions, the applicant reserves the right to make them the subjectmatter of independent claims or divisional declarations. They mayfurthermore also contain independent inventions which have aconfiguration that is independent of the subject matters of thepreceding dependent claims.

Further, elements and/or features of different example embodiments maybe combined with each other and/or substituted for each other within thescope of this disclosure and appended claims.

Still further, any one of the above-described and other example featuresof the present invention may be embodied in the form of an apparatus,method, system, computer program, computer readable medium and computerprogram product. For example, of the aforementioned methods may beembodied in the form of a system or device, including, but not limitedto, any of the structure for performing the methodology illustrated inthe drawings.

Even further, any of the aforementioned methods may be embodied in theform of a program. The program may be stored on a computer readablemedium and is adapted to perform any one of the aforementioned methodswhen run on a computer device (a device including a processor). Thus,the storage medium or computer readable medium, is adapted to storeinformation and is adapted to interact with a data processing facilityor computer device to execute the program of any of the above mentionedembodiments and/or to perform the method of any of the above mentionedembodiments.

The computer readable medium or storage medium may be a built-in mediuminstalled inside a computer device main body or a removable mediumarranged so that it can be separated from the computer device main body.Examples of the built-in medium include, but are not limited to,rewriteable non-volatile memories, such as ROMs and flash memories, andhard disks. Examples of the removable medium include, but are notlimited to, optical storage media such as CD-ROMs and DVDs;magneto-optical storage media, such as MOs; magnetism storage media,including but not limited to floppy disks (trademark), cassette tapes,and removable hard disks; media with a built-in rewriteable non-volatilememory, including but not limited to memory cards; and media with abuilt-in ROM, including but not limited to ROM cassettes; etc.Furthermore, various information regarding stored images, for example,property information, may be stored in any other form, or it may beprovided in other ways.

Example embodiments being thus described, it will be obvious that thesame may be varied in many ways. Such variations are not to be regardedas a departure from the spirit and scope of the present invention, andall such modifications as would be obvious to one skilled in the art areintended to be included within the scope of the following claims.

LIST OF REFERENCE CHARACTERS

-   B Image-   OB Orientation image-   NB Navigation image-   M Monitor-   10 System-   11 Monitor control module-   12 Metadata-   14 Display parameters cm What is claimed is:

1. A method for displaying at least one medical image from a volumedataset on a monitor of a computer-aided device with, in addition to theat least one medical image, orientation images from the volume datasetof the at least one medical image being displayed, the methodcomprising: determining or providing an orientation measurement;applying the determined or provided orientation measurement to thevolume dataset in order to select, from the volume dataset, orientationimages which correspond to the determined or provided orientationmeasurement; and displaying the at least one medical image together withthe selected orientation images.
 2. The method as claimed in claim 1,wherein the orientation measurement is selectable from a set whichcomprises: a distance-related orientation measurement, with a distanceof the orientation measurement identifying a distance between arespective orientation image and the at least one medical image; and ananatomy-related orientation measurement.
 3. The method as claimed inclaim 2, wherein the distance of the distance-based orientationmeasurement is constant or is able to be set to grow in accordance witha configurable growth parameter.
 4. The method as claimed in claim 2,wherein the anatomy-related orientation measurement is based on ananatomic model provided, with all or selected images of the volumedataset being assigned an electronic anatomic code.
 5. The method asclaimed in claim 1, wherein the orientation measurement is determinedautomatically on the basis of metadata established for the volumedataset.
 6. The method as claimed in claim 1, further comprising:displaying a navigation image, orthogonal to the at least one medicalimage or to the orientation images, wherein the displayed orientationimages and the displayed image are identified in their spatial position.7. The method as claimed in the claim 6, wherein the display of thenavigation image is interactive, so that navigation can be undertaken inthe volume dataset by way of the navigation image with, on activation ofan area on the navigation image, at least one of the associated imageand orientation image automatically being loaded.
 8. The method asclaimed in claim 6, wherein at least one of the navigation image istwo-dimensional or three-dimensional, and an anatomic structure islabeled and assigned to the navigation image.
 9. The method as claimedin claim 6, wherein the displayed image and the displayed orientationimages include a reference to their respective spatial position in thenavigation image.
 10. The method as claimed in claim 1, wherein theorientation images will be displayed automatically and almost at thesame time as the image.
 11. The method as claimed in claim 1, wherein atleast one of the display of the orientation images and the display ofthe navigation image is initiated by a user interaction during or afterthe display of the image.
 12. The method as claimed in claim 1, whereindisplay parameters for display of at least one of the image, theorientation images and a navigation image are able to be configured. 13.The method as claimed in claim 1 wherein at least one of the image andthe orientation images are three-dimensional image datasets with apreselectable slice thickness.
 14. The method as claimed in claim 13,wherein the slice thickness of the image is selectable separately fromthe slice thickness of the orientation images.
 15. A monitor controlmodule for controlling display of a medical image from a volume dataseton a monitor of a computer-aided device, the display being controllablesuch that, in addition to the medical image, a number of orientationimages from the volume dataset of the image will be displayed,comprising: a determination module designed to determine or to providean orientation measurement; a control module designed to apply theorientation measurement of the determination module to the volumedataset, in order to select, from the volume dataset, the orientationimages that correspond to the orientation measurement determined orprovided; and a display module to present the medical image togetherwith the selected orientation images on the monitor.
 16. A system fordisplaying at least one image from a volume dataset, comprising: amonitor, intended for display of images and assigned orientation images;and a monitor control module as claimed in claim 15, the monitor controlmodule including a data link to the monitor and able to include a userinterface.
 17. A computer program product loadable or loaded into amemory of a computer, including computer-readable commands for executingthe method as claimed in claim 1 when the commands are executed on thecomputer.
 18. The method as claimed in claim 2, wherein the orientationmeasurement is determined automatically on the basis of metadataestablished for the volume dataset.
 19. The method as claimed in claim2, further comprising: displaying a navigation image, orthogonal to theat least one medical image or to the orientation images, wherein thedisplayed orientation images and the displayed image are identified intheir spatial position.
 20. The method as claimed in the claim 19,wherein the display of the navigation image is interactive, so thatnavigation can be undertaken in the volume dataset by way of thenavigation image with, on activation of an area on the navigation image,at least one of the associated image and orientation image automaticallybeing loaded.
 21. A computer readable medium including program codesegments for, when run on a computer, executing the method as claimed inclaim 1.